Relaxor-normal ferroelectric phase transition and significantly enhanced electromechanical strain behavior in Bi(Ni1/12Ti1/2)O-3-PbTiO3-Pb(Mg1/3Nb2/3)O-3 ternary system close to the morphotropic phase boundary
Relaxor-normal ferroelectric phase transition and significantly enhanced electromechanical strain behavior in Bi(Ni1/12Ti1/2)O-3-PbTiO3-Pb(Mg1/3Nb2/3)O-3 ternary system close to the morphotropic phase boundary
复制标题
Bi(Ni1/12Ti1/2)O-3-PbTiO3-Pb(Mg1/3Nb2/3)O-3三元体系中接近同形相界的弛豫-正态铁电相变和显着增强的机电应变行为
DOI：
10.1016/j.jeurceramsoc.2015.05.033
复制
发表时间：
2015
影响因子：
5.7
通讯作者：
Zuo Ruzhong
中科院分区：
文献类型：
--
作者：
Zheng Donggeng;Zuo Ruzhong
在新型钙钛矿型（0.65− x）Bi（Ni 1/2 Ti 1/2）O3-0.35PbTiO3-xPb（Mg 1/3 Nb 2/3）O3陶瓷中发现了一个伪立方到四方相的相变，并伴随着弛豫-正常铁电相变。在0.4 <x< 0.6的范围内确定了准同型相界，其中达到最大准静态33 = 550 pC/N。然而，在6 kV/mm（动态33 * = 583 pm/V）下，在0.15 ≤x≤ 0.4范围内产生了0.35%的大应变平台。特别是d33 * 和应变滞后与Pb（Mg_（1/3）Nb_（2/3））O_3含量、场强和信号频率密切相关。随温度变化的测量结果表明，增强的电应变不仅出现在冻结温度Tf附近，而且出现在遍历到铁电相变温度Tfr附近，这两者都归因于可逆场诱导遍历到铁电相变。一个有趣的发现是，更相似的自由能遍历和铁电相之间的Tfr附近带来了较小的驱动场和应变滞后，但较低的最大应变。
A pseudo-cubic to tetragonal phase transformation was found to be accompanied by a relaxor-normal ferroelectric phase transition in new perovskite-type (0.65− x)Bi(Ni1/2Ti1/2)O3–0.35PbTiO3–xPb(Mg1/3Nb2/3)O3ceramics. A morphotropic phase boundary was identified in the range of 0.4 <x< 0.6 where the maximum quasi-staticd33= 550 pC/N was achieved. However, a large-strain platform of ∼0.35% was generated under 6 kV/mm (dynamicd33* = 583 pm/V) within 0.15 ≤x≤ 0.4. Particularly, thed33* and the strain hysteresis were found to be closely related with the Pb(Mg1/3Nb2/3)O3content, field magnitude and signal frequency. The temperature-dependent measurement demonstrated that enhanced electrostrains appeared not only near a freezing temperatureTf, but also near an ergodic to ferroelectric phase transition temperatureTfr, both of which are ascribed to a reversible field induced ergodic to ferroelectric phase transition. An interesting finding would be that more similar free energies between ergodic and ferroelectric phases nearTfrhave brought about smaller driving fields and strain hysteresis but lower maximum strains.